Features that are considered purely decorative flourishes in watchmaking today were once practical necessities. The use of guilloché improved legibility by adding depth to the dial. The process of bluing steel for watch hands strengthened the underlying material. And the tourbillon counteracted the effects of gravity on timekeeping accuracy. What do these horological details have in common? They were all developed, or at the very least refined, by Abraham-Louis Breguet, who is considered one of the greatest watchmakers of not only his era but of all time. He founded his eponymous maison in 1775, and some of the greatest mechanical marvels in watchmaking have emerged from it in the ensuing centuries. The Reference 3050BA ranks among the most collectible Breguets because it showcases what the maison has done best: combining restrained elegance with a compact perpetual calendar and moonphase.